999972501608537 has 4 divisors (see below), whose sum is σ = 999975040074660. Its totient is φ = 999969963142416.

The previous prime is 999972501608513. The next prime is 999972501608569. The reversal of 999972501608537 is 735806105279999.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 674770031984896 + 325202469623641 = 25976336^2 + 18033371^2 .

It is a cyclic number.

It is not a de Polignac number, because 999972501608537 - 2⁸ = 999972501608281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999972501608137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1268642078 + ... + 1269430055.

It is an arithmetic number, because the mean of its divisors is an integer number (249993760018665).

Almost surely, 2^{999972501608537} is an apocalyptic number.

It is an amenable number.

999972501608537 is a deficient number, since it is larger than the sum of its proper divisors (2538466123).

999972501608537 is a wasteful number, since it uses less digits than its factorization.

999972501608537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2538466122.

The product of its (nonzero) digits is 2314720800, while the sum is 80.

The spelling of 999972501608537 in words is "nine hundred ninety-nine trillion, nine hundred seventy-two billion, five hundred one million, six hundred eight thousand, five hundred thirty-seven".